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I believe it to be alright. A good source for info like that is enginuity.org forums. I think that they refer to it as a stage 2.5 upgrade and you will need a retune. The car will build boost beyond what you have it set to now only because of cooler and denser air coming in. Also winter is right around the corner so you may see a 1 to 2 pound boost fluctuation. Good if your car is ready for it.....bad if it isn't.

As was stated, the bigger TMICs flow a bit better than stock. That means the turbo can work at a lower pressure ratio for a given boost at the manifold, the wastegate tables will need to be adjusted to compensate.

Other than possible overboosting, it should be fine. The better cooling should allow you to run more boost, leaner afr, or more timing over the Stage 2 map you are currently running.

I don't see major adjustments needed unless you went with a FMIC. Probably just adjust the WGDC/Continuous/Burst a bit if it's oscillating, and boost table if your running alot more (3-4 PSI) boost than before but hitting target and it is steady.

If Boost goes up by 1 PSI or so, but the dynamics stay the same, I'd say it's probably fine and just a result of less pressure drop.

I just put an STI TM on my car today and will be doing some tuning with it tomorrow. I'll let you know if I change anything.

The difference between the stocker and the majority of bar and plate designs (like the majority of the ebay ones) is that there is a .2 psi pressure drop vs a 2-3 psi pressure drop on the stock intercooler. What this means is you can realistically run 2-3 psi more boost and the turbo is in the same range as it was before since it is not having to work as hard. This means the ability to run more boost while keeping the turbo in its efficiency range. The difference in cooling is going to be minimal until you go to a front mount. So, as others have said, adjust wgdc and MAYBE turbo dynamics.

I'm assuming going from a WRX to STI intercooler is why I started to overshoot my boost target. I adjusted the TD table to lower the speed that boost increases. I also notice in the logs I don't need nearly as much WDGC as the Stock ECU had dialed in to make target boost.